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Reply With QuoteProbably unburned fuel leaking out from the exhaust.
Slabmaster
Lower Unit Leaking Fluid - Help
I recently went on a trip to Reelfoot lake. When I pulled the boat out of the water, I noticed the fluid leaking from my lower unit. It looks like it is leaking from a specific hole (see pictures). Does anyone know the purpose of this hole or why my fluid would be leaking from it? I took a closeup in one picture and tried to make a red circle where the hole is located in the other. Any help would be appreciated. Thanks!
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Probably unburned fuel leaking out from the exhaust.
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I just replaced the lower unit on my Yamaha because we could not get the seal to seat properly, but mine was leaking out the prop shaft. I don't know what the hole is you circled, but I would not have thought it was an exhaust port on the front of the foot.
Mark 1:17 ...I will make you fishers of men
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I am no pro, but the fluid looks milkey, which would be a sign of water in the system. I know Reelfoot is shallow lake so I would bet you hit something and either caused it to leak or enhanced the leak, either way I would take it apart and find the leak and refill with the proper oil. Thay recommend you change the oil in the lower unit once a year anyway. I had a old 9.5hp Evinrude that had the same problum and had to by new seals, it is was important to use the correct gasket sealer on mine also, it took me 3 trys to stop the leak but it worked. Good luck
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It's a water drain for the lower unit.Originally Posted by SeaRay
I just replaced the lower unit on my Yamaha because we could not get the seal to seat properly, but mine was leaking out the prop shaft. I don't know what the hole is you circled, but I would not have thought it was an exhaust port on the front of the foot.
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Be on the safe side and change the oil in your lower unit. Be sure to use new gaskets on the drain and vent plugs. As mentioned it could just be unburned fuel but you want to be sure.
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Bill H. PTC USN Ret
Chesapeake, Va
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First pull bottom plug on lower unit oil cavity and let a little bit drain into a clean cup. If not milky I would bet you did a lot of low speed running on the stump field and it's unburned fuel mixed with lake water coming from the exhaust side.
Slabmaster
Thanks guys. I planned on attacking this today, but a little under the weather. CRAY, that's the only speed we went all week, SLOW! So, I bet you are on to something there. Thanks!
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OkOk
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Smell the oil it will either smell like two stroke oil ( unburnt oil leaking from exhaust) or gear oil(leaking from lower unit) it's pretty common for oil to leak out of exhaust. If it is gear oil I'd service the lower unit and check for water contamination. If so take it in and have it pressure tested to check for a bad seal.
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